Performance aspects of gas-operated pressure balances as pressure standards

Sutton, C M; Fitzgerald, M P

doi:10.1088/0026-1394/46/6/007

Cited by 18 publications

(13 citation statements)

References 13 publications

(33 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the system used, the ratio of the two latter can be assessed to 1 m. Under the assumption that the relative effective area of the piston has a dependence on the piston height, a, that is comparable to those of other piston gauges, which has been assessed to 0.4 ppm/mm (Ref. 38), the fluctuations in the pressure provided by the piston gauge, dP PG , due to variations of the height of the piston, can be estimated from dP PG ¼ a P PG dh. Since it was estimated that a typical fluctuation of the pressure to which the system was filled during valve state i (i.e., dP 0 system ) was 5 Pa, this shows that the fluctuations of the filling pressure due to cycle-to-cycle variations of P 0 system , i.e., dP PG , can be estimated to be 2 mPa.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Gas modulation refractometry for high-precision assessment of pressure under non-temperature-stabilized conditions

Silander

Hausmaninger

Zelán

et al. 2018

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

View full text Add to dashboard Cite

The authors report on the realization of a novel methodology for refractometry—GAs modulation refractometry (GAMOR)—that decreases the influence of drifts in Fabry Perot cavity refractometry. The instrumentation is based on a dual Fabry-Perot cavity refractometer in which the beat frequency between the light fields locked to two different cavities, one measurement and one reference cavity, is measured. The GAMOR methodology comprises a process in which the measurement cavity sequentially is filled and evacuated while the reference cavity is constantly evacuated. By performing beat frequency measurements both before and after the finite-pressure measurement, zero point references are periodically created. This opens up for high precision refractometry under nontemperature-stabilized conditions. A first version of an instrumentation based on the GAMOR methodology has been realized and its basic performance has been scrutinized. The refractometer consists of a Zerodur cavity-block and tunable narrow linewidth fiber lasers operating within the C34 communication channel (i.e., around 1.55 μm) at which there are a multitude of fiber coupled off-the-shelf optical, electro-optic, and acousto-optic components. The system is fully computer controlled, which implies it can perform unattended gas assessments over any foreseeable length of time. When applied to a system with no active temperature stabilization, the GAMOR methodology has demonstrated a 3 orders of magnitude improvement of the precision with respect to conventional static detection. When referenced to a dead weight pressure scale the instrumentation has demonstrated assessment of pressures in the kilo-Pascal range (4303 and 7226 Pa) limited by white noise with standard deviations in the 3.2N−1/2–3.5N−1/2 mPa range, where N is the number of measurement cycles (each being 100 s long). For short measurement times (up to around 103 s), the system exhibits a (1σ) total relative precision of 0.7 (0.5) ppm for assessment of pressures in the 4 kPa region and 0.5 (0.4) ppm for pressures around 7 kPa, where the numbers in parentheses represent the part of the total noise that has been attributed to the refractometer. As long as the measurement procedure is performed over short time scales, the inherent properties of the GAMOR methodology allow for high precision assessments by the use of instrumentation that is not actively temperature stabilized or systems that are affected by outgassing or leaks. They also open up for a variety of applications within metrology; e.g., transfer of calibration and characterization of pressure gauges, including piston gauges.

show abstract

Section: Discussionmentioning

confidence: 99%

“…38 Measurements of the long-term stability have revealed stabilities approaching 1 Â 10 À6 per decade.…”

Section: E105-4 Silander Et Almentioning

confidence: 99%

Gas modulation refractometry for high-precision assessment of pressure under non-temperature-stabilized conditions

Silander

Hausmaninger

Zelán

et al. 2018

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

View full text Add to dashboard Cite

show abstract

“…A more detailed description is given in [3]. As shown in Figure 1, a gas-operated pressure balance (or piston gauge) consists of a loaded piston in a close-fitting vertical cylinder.…”

Section: Gas-operated Pressure Balancesmentioning

confidence: 99%

“…For early generation gas-operated pressure balances, the shortterm stability of the pressure difference between two pressure balances has been measured to have a 0.7 mPa standard deviation at 100 kPa for an 8 s average, corresponding to a relative standard deviation of 7 × 10 -9 [3]. This is equivalent to a relative weighing accuracy for mass m of about 1 × 10 -8 , if m is two-thirds of the total mass of the piston and its load.…”

Section: Pressure Balance Watt Balance Conceptmentioning

confidence: 99%

The concept of a pressure balance based watt balance

2010

View full text Add to dashboard Cite

The possibility of a watt balance based on gasoperated pressure balances is discussed in the context of both a measurement of the Planck constant and a non-artefact realisation of the kilogram. Gasoperated pressure balances meet several key requirements of a watt balance. For example, two pressure balances in combination act as a highprecision mass comparator for the weighing mode while a single pressure balance can be used to move the coil through the magnetic field in a strictly vertical manner for the dynamic mode.

show abstract

“…In the traditional working mode, the loaded piston rotates freely inside the cylinder, behaving as an aerodynamic bearing. Sutton and Fitzgerald have discussed the aspects of rotated gas-operated pressure balances that affect their performance [22]. It is recommended that the piston gauge be operated with a small, reproducible falling rate [14].…”

Section: Introductionmentioning

confidence: 99%

Realization of ppm level pressure stability for primary thermometry using a primary piston gauge

et al. 2020

View full text Add to dashboard Cite

To achieve an uncertainty of 0.25 mK in single-pressure refractive-index gas thermometry (SPRIGT), the relative pressure variation of He-4 gas in the range 30 kPa to 90 kPa, should not exceed 4 ppm (k=1). To this end, a novel pressure control system has been developed. It consists of two main parts: a piston gauge to control the pressure, and a home-made gas compensation system to supplement the micro-leak of the piston gauge. In addition, to maintain the piston at constant height, a servo loop is used that automatically determines in real time the amount of extra gas required. At room temperature, the standard deviations of the stabilized pressure are 3.0 mPa at 30 kPa, 4.5 mPa at 60 kPa and 2 mPa at 90 kPa. For the temperature region 5 K-25 K used for SPRIGT in the present work, the relative pressure stability is better than 0.16 ppm i.e. 25 times better than required. Moreover, the same pressure stabilization system is readily transposable to other primary gas thermometers.

show abstract

Performance aspects of gas-operated pressure balances as pressure standards

Cited by 18 publications

References 13 publications

Gas modulation refractometry for high-precision assessment of pressure under non-temperature-stabilized conditions

Gas modulation refractometry for high-precision assessment of pressure under non-temperature-stabilized conditions

The concept of a pressure balance based watt balance

Realization of ppm level pressure stability for primary thermometry using a primary piston gauge

Contact Info

Product

Resources

About